HD404639R Datasheet, PDF (41/135 Pages) Renesas Technology Corp – 4-Bit Single-Chip Microcomputer

System clock select register 2 (SSR2: $02A)
Bit
Initial value
Read/Write
Bit name
3
0
W
SSR23
2
0
W
SSR22
1
0
W
SSR21
0
0
W
SSR20
HD404639R Series
SSR23
0
1
SSR22
0
1
0
1
System clock selection
Selected from 400 kHz,
800 kHz, 2 MHz, 4 MHz^*2
3.58 MHz
8 MHz^*2
7.16 MHz
SSR21
0
1
SSR20
0
1
0
1
System clock division ratio^*1
1/4 division
1/8 division
1/16 division
1/32 division
Notes: 1. The DTMF frequencies are not affected by the setting of the system clock division ratio.
2. Refer to system clock select register 1 (SSR1) of figure 24.
Figure 26 System Clock Select Register 2 (SSR2)
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